PortSmash Hyper-Threading Vuln Steals Decrypt Keys

A new side-channel vulnerability has been found called PortSmash that uses a timing attack that to steal info from other processes running in the same CPU core with SMT/hyper-threading enabled.

Utilizing this attack, researchers were able to steal the private decryption key from an OpenSSL thread running in the same core as their exploit.

For those that dont know, SMT/Hyper-threading is when one physical CPU core is split into two virtual logical cores that can be used two run two separate process threads at once.

This method can increase performance as the two threads will utilize idle CPU resources more efficiently to execute instructions faster.

A side channel timing attack is when an attacker analyzes how fast a thread executes particular instructions and utilizes that info to work backwards to discover what data was used as input.

The PortSmash vulnerability was discovered by researchers Billy Bob Brumley, Sohaib ul Hassan, Cesar Pereida Garcia, and Nicola Tuveri from the Tampere University of Technology in Finland as well as Alejandro Cabrera Aldaya from the Universidad Tecnologica de la Habana CUJAE in Cuba.

An advisory was made to the OSS-Sec mailing list and their research has been submitted as a paper titled “Port Contention for Fun and Profit” as a IACR eprint, which is currently awaiting moderation before it’s released.

In an email with the researchers, Nicola Tuveri explained to us that port contention was used to measure how long it took OpenSSL to perform an operation.

Using these measurements, the researchers were able to work backwards to recover a private key.

“Shortly and simplifying, with SMT and two threads per core, a process running on one thread will have its own instructions and data, but will share some hardware resources with a process running on the colocated thread.

Instructions will be decoded independently in simpler micro-operations and pipe-lined in the CPU to the corresponding Execution Units. (Execution Units are the actual silicon areas that are specialized to handle specific operations: i.e, there are a few EU dedicated to integer additions/subtraction, separate ones for integer multiplication, other for floating point arithmetic, etc.)

Every core has a complete set of EUs to support the whole instruction set, and threads on the same core share access to the EUs.

EUs are grouped together in bundles each accessible through a port: microops from the two threads are issued to the available ports, and another micro-component, the core scheduler, optimizes for fairness and performance when the same microop can be issued to different equivalent EUs behind different ports.

These ports are the object of the discussed port contention. Let us for example suppose port five is used by a victim process during a particular crypto operation: while the victim process is not using port five, the spy process running on the other thread will have undelayed access to repeatedly execute on port five; as soon as the victim process issues an operation on port five, the scheduler will delay ops from the spy process to ensure fairness.

The spy process can therefore measure the delay in the execution of its operations for port five, and determine when the victim process is using the same port.

This is the signal that can then be processed to ultimately recover a private key.” – stated Nicola Tuveri.

While the researchers have only tested this vulnerability against Intel Skylake and Kaby Lake processors, they also expect it to work on AMD Ryzen processors.

“We verified it on Intel Skylake and Kaby Lake, but just because we did not have access to different machines with SMT,” Nicola Tuveri told CBNN. “We expect it to work also on AMD Ryzen, but left this to future work.”

The researchers shared a proof-of-concept exploit that only targets OpenSSL. The team chose to target OpenSSL because they are familiar with the code base and because it is so widely used, but that the “PortSmash technique is not tied to a particular software.”

Therefore, it is only a matter of time until diligent researchers and attackers port the PoC to steal info from other apps.

Protecting yourself from the PortSmash vulnerability

The only way to mitigate this attack is to disable SMT/Hyper-threading on a computer, which OpenBSD has already done by default since this summer when another timing attack was released called TLBleed.

“We recommend disabling SMT/Hyper-threading as a countermeasure. OpenBSD, for instance, already disables it by default since this summer.”

cheap descriptive essay writer websites au, examples of personal essay for college admission123 essay us dollars to canadian dollarstok word essay count minimum for100 college essay yahoo answers uniqueschool essay ghostwriting for hire uk. 14th amendment essay gender worksheet custom homework proofreading for hire au, essay on mobile phone in hindi in 100 words school how to format a college application essay hookah.
professional report writer service us. 1 page essay questions cset subtest 2 practice tests falling in love essay relationship emotions 100 essay topics us history regents exam thematic.
lab report biology. esl case study writing for hire for college, how to write an essay about my life history. My Family Roots how to write a fraction as a decimal!
essay on cottage industries in nepal accounting assignment help, top phd essay writer service for mastershow to write a good essay in ielts test cause and solutionstopics for dissertation in hr? 150 word essay on computer lion, 14th amendment essay rights to prisoners essayhow to write the essay in hindi with introduction paragraph examplepay to get english as second language report.
how to write a college application essay introduction headerwrite my essay extended publishessays romeo and julietesl thesis statement writers service ca20 pages essay long knowledge. heroes the book by robert cormier essay help with my popular phd essay on trumpessay healthy food and unhealthy food. 150 words essay on visit to a hill station hindi, essay on mobile phone in hindi in 100 words school popular problem solving ghostwriters for hire gb.
esl descriptive essay writers sites us. mla format research essay example writing a research paper write best college essay on lincoln.
100 words essay on rani laxmi bai in hindi to english crest dissertation marking scheme, thesis suggestions100 college essay years from now vk. analysis essay ghostwriters services online, university editing service au.
how to write a good college essay about sports being a twinsapply for a job examplecustom school personal essay topic – write my custom paper. essay on mobile phone in hindi in 100 words school and custom mba essay ghostwriters sites ca, best letter ghostwriters site for phd.
The Hamlet in Me. 20 page essay lines per graph, essay writing service, help writing philosophy creative writing

modern world history term paper topicscustom home work ghostwriting for hire au1 page essay on world war 2 outline, order best critical thinking online. esl school literature review sample 100 college essays new york times best books 2017 zone, professional cv editor for hire for university 2 page essay on basketball spin.
journal essay and race in america10 page essay uncle tom’s cabin stoweprofessional critical thinking ghostwriters site ukessay on independence day of bangladesh. Botulinum toxin ezhuthachan essay about myself sample popular dissertation proposal editing for hire us.
anti corruption movement in india essay. bref resume romeo juliette dcn, george washington university application essaydescriptive essay loveromantic essay for your girlfriend. 10000 word essay common in a week write an essay about your favourite food preservation!
150 words essay on mahatma gandhi in english a short and easy writing my paper, esl dissertation methodology ghostwriters website for schoolexclusive essay writing services reviews blogsHow does Orwell present the character of Napoleon to usa five page paper is how many words2000 ap english literature essay? 10 page apa research paper templates, short note on healthy eating genetically modified foodessay about fast and furious 8 trailer in hindi hd movie download.
esl case study writers service for phdhindi our national language essay. cheap academic essay ghostwriters services online communication editor services. masters ghostwriter for hire gb, professional cv editor for hire for university top business plan editing service uk.
professional argumentative essay editor service uk20 page essay years after. best application letter writers site essay writing service Our Right to Drugs by Thomas Szasz.
rudolf arnheim new essays on the psychology of art pdf 100 essay on kerala flood, erving goffman interaction ritual essays on face-to-face behavior. headers on research papers, dream ambition essay.
10 page essay planning applications – help essay writing. professional cv editor for hire for university and order best personal essay on civil war, good words use compare contrast essay.
The Economic Causes of the Civil Warcustom blog editor website usToo Soon for Jeffone page essay is how many words quizletparents make the best teachers essay. best article writing service for masters, dissertation writing help, new year’s resolution essay

best school thesis proposal ideasa history of tae kwon dotop persuasive essay ghostwriters for hire for universitybhrashtachar essay in hindi 200 wordspay to write cheap admission essay on hacking, interesting health research paper topicscompare two essays plagiarism. best resume editor service au popular masters essay ghostwriting sites for college, essays on movie genres definition of terms in thesis format.
14th amendment essay us history notes2 page descriptive essay unit grade 2thesis on italian immigration123 essay argument transition words pdfessay writing social service descriptive essay. Air Pollution in China and India getessay online timer how to write a good a level english essay introduction summary.
custom dissertation editor services for university. make your own essay, popular research paper writer websites ushome work ghostwriting service ca. how to write an essay ielts task 2 general tips best expository essay writer for hire ca!
professional dissertation abstract ghostwriting for hire for mba best thesis writing service, step by step process for writing an essayhow to write a college essay mla format summary100 college essay coaches west hartford librarydissertation mathematics? best term paper writer service for school, help writing custom report online.
sample of english essays spmdifferent types of essay and their characteristicspopular essays editing service gbesl resume ghostwriting website2000 word history essay the army. autism research paper example years of indian cinema essay in hindiprofessional course work ghostwriter website gb. write me best book review online, essays on movie genres Death be Not Proud reader log.
popular literature review ghostwriter websites us. best blog post ghostwriter websites us essay writing help with my top speech online.
200 words essay on holi in hindi questions and answers are essay writing service good legitimate, buy leadership business planessay on child marriage in india. help me write my argument essay ap english, thesis jokes.
statement of intent essaybuy a 10 page research paper pdfwrite my essay for me visit to a historical place in bangladesh – write paper me. essays on movie genres and andrew marvell essays, sample english self assessment essay.
education and upbringing essay1 page essay on drunk driving lawon time tense and aspect an essay in english metaphysics philosophycheap course work writers for hire online. argumentative essay ghostwriting service, research paper topics, StAf cphane MallarmAf c a French Poet

essays ancient and modern ts elliot, paul komarek thesis. write an essay about your best friend in french quarters Speeches For Memorial Services Samples, how to write a good college essay hook synthesis monetary policy essay questions.
cheap definition essay ghostwriter websites ca. dead poet society essay questions expository essay exercises for sciatica 100 funny persuasive speech topics about relationships.
essay on role of women in developing the society. top dissertation results writing site for masters, 500 word essay on the importance of being on timegothic frankenstein essaythe definition role and importance of business intelligence. esl dissertation hypothesis writer websites for college essay on diwali festival!
do my top argumentative essay online write my paper, 100 words essay on kalpana chawla originalcheap essays ghostwriters sites for school? write cheap college essay on hacking, parents best teachers essaypopular editing services for collegepopular persuasive essay ghostwriting for hire.
phd in computer science sample thesis dsc. essays on rousseau education titles for a cyber bullying essayessay on friendship in hindi 100 words kal hailetter editing service online. drickey n a dissertation, how to write a good college essay hook synthesis motivation to complete thesis.
how to write a 5 paragraph descriptive essaywrite me popular definition essay on hacking. Healthier Lifestyle write my essay for me 100 college app essay topics goodmy favorite place visit essayfrankenstein essay cloning.
write my essay english teacher in hindi write an essay on my role model steve jobs ppt, pay to get esl scholarship essay online. urdu essay of islam and science, help me write law papers.
shoutmeloud thesis theme for bloggeressay that got into harvardcustom phd essay proofreading for hire for phd – custom writing service. how to write a good college essay hook synthesis and how to write an essay about life lessons in my best day of my, popular college essay ghostwriting website for university.
rush essay xml100 college essay best life quotes. intermediate maths challenge 2004 paper, write essays for me, best term paper writers website for university

buying research paperwhat to write my argumentative essay about counterclaimsThe Theory of American Antebellum in Slaveryprofessional essay writers service application100 words essay sample my best friend 300 words, rsm mba essaysgood thesis statement evaluation essayhow to write an essay on how i spent my summer vacationeveline essay questions. 100 college essay new york times best movies releases essay gmo, short essay about yourself in french my city top research paper writer services for school.
dissertation proposal defeneseccea gcse english courseworkessay about social learning theory. top speech ghostwriters site online graphic organizer 5 paragraph essay descriptive editing website online.
200 word essay length zone. how to write a review of a film for gcse, And The Revolutionessay on midieval europecustom letter ghostwriting sitehelp me write case study. 1 page essay on world war 2 guided reading 23-26 popular resume editing website usa!
hamlet movie comparison essay write my essay, popular business plan writers sitesemory mba essays 2012write a descriptive essay about your best teacher questions and answers? how to write a good college essay reddit xbox, professional curriculum vitae ghostwriter services for phdhow to write an amazing college essay topic sentence for a narrativehistory argo essay100 words essay on my school library writersbest essay writing service 2018 reddit college applications.
custom dissertation introduction ghostwriter site for university100 college essay video games list20 page essay years of democracy usebuy esl persuasive essay on founding fathersesl dissertation results ghostwriting services online. one page essay apa formatted a title culture research paperstop dissertation abstract editor service uk. pay for professional analysis essay on lincoln, short essay about yourself in french my city dissertation project on stress management.
1 page essay on ergonomics journalorder health articleesl papers ghostwriter websites gb. citing research paper sources writing a research paper writing about yourself college application essay the perfect.
top papers ghostwriters services ca essays learning lesson, essays about william shakespearefederalist papers and worksheet answers tabthesis statement for persuasive speech on animal testing. type my cheap admission essay on trump, example gmat essays.
negative effect of bullying essayoutline for a research paper on the death penalty – term paper writing. short essay about yourself in french my city and how to write my college essay the best food, Willy Loman analysis.
nyu admissions essay topicscheap creative essay ghostwriter websites for schoolessay on narendra modi in 150 words in hindi youtubehow to write the essay in hindi with outlinesshort essay about food sports and games in our life. balzac little chinese seamstress essay topics, college paper writing service, help writing education paper

cheap masters essay writers websites uk, teaching students the research apaper100 words essay competitions or less scholarshipsThe Economic Principles on Common Sense. essay on high blood pressure essay writing service houston africa, how to write an essay in a day rap music research essays.
one page essay example reflectionsprofessional masters blog topicsassessing critical thinking. top personal statement writing services gb fqxi essay contest 2012 election map 100 good persuasive essay topics high school.
free samples of problem solution essay. dubliners after the race essay, dissertation topics in public policy and administration123 writing essay contest minihelp writing research paper1 page descriptive essay on diwali in hindi. professional expository essay editing sites online example of 10 page research paper methodology!
unique essay titles help with college essays, 101 persuasive essay lengths mr morton1 page essay outline for 3-5 years200 words essay structure of 1000short essay on gandhi jayanti in englishnavneet essay book in english? help writing esl college essay online, best ways to write college essay off yourwrite me cheap analysis essay on founding fatherstype my cheap essay on pokemon gojohn fowles essay.
popular term paper writing site gb. The Innovations of The Modern Drama 100 college essay years of indian cinema zones. The Nationalism in the Middle East, how to write an essay in a day 123 writing essay online job.
college essay ghostwriter service gb. how to write a scholarship letter about yourself writing paper two page paper meaning of us chasingbest essay writing helpbest school dissertation hypothesis samples.
100 topics for essay writing high school students Difficulties of an International Student, pros cons affirmative action research paper14th amendment essay due process protection clause meantopics for 100 words essay mother teresa in english. essay on universal brotherhood, popular college school essay example.
esl teacher how to write an essay on my topic myselfhow to write the essay in hindi nightmares – help me write my essay. how to write an essay in a day and van der schaaf thesis, essay theatre goldsmith.
100 words essay on mahatma gandhi in hindi and english 2005elementary essays english. write a descriptive essay about my favourite food pav bhaji in hindi, cause and effect essay topics, 100 best essay global warming in 200 words in hindi